1. Technical Field
The invention disclosure relates to an image forming apparatus, and particularly relates to a recording head that ejects recording ink.
2. Description of the Related Art
Inkjet recording apparatuses are used as image forming apparatuses such as printers, fax machines, copy machines, and plotters. A serial type image forming apparatus is one of the inkjet recording apparatuses, and is configured to form (records) images on a medium to be recorded on (which includes recording paper, transfer paper and other recording media and is hereinafter referred to as “sheet” although the material is not limited to paper) using a droplet ejection head or a recording head that is mounted on a carriage for ejecting recording liquid (e.g. ink) from a nozzle while moving the carriage in a main scanning direction.
This type of inkjet recording apparatus has been mainly used as a single-function apparatus such as a printer for personal use. If a carriage of such an inkjet recording apparatus having a recording head mounted thereon gets out of order, the apparatus is sent to a repair shop so as to be disassembled for repairing or replacing the carriage.
In these years, so-called multi-function image forming apparatuses having two or more of a printer function, a fax machine function, and a copy machine function are being developed and coming into practical use. Different from single-function apparatuses, multi-function type image forming apparatuses can not be easily sent to repair shops. Therefore, multi-function apparatuses are preferably configured such that a service person can make repairs on-site by replacing parts.
An example of image forming apparatuses that allow part replacement is disclosed in Patent Document 1, which comprises detachable plural blocks. Each block is responsible for a specific function and has connection means to be connected to the other blocks. The blocks are classified into plural groups according to the configuration of the connection means. The blocks in the same groups have the same type connection means. One block having a desired function is selected from each group, and the selected blocks are connected to each other through the connection means.
[Patent Document 1] Japanese Patent Laid-Open Publication No. 2001-219618
In the above-described image forming apparatus, a maintenance recovery mechanism for maintaining and restoring a condition of a recording head is formed as a block integral with a recovery block including a suction cap, a blade, a recovery motor, and a recovery pump. The recovery block can be removed by being pulled out to the upper side from the apparatus body.
Generally, in image forming apparatuses provided with a carriage having a recording head mounted thereon, a guide rod (guide shaft) for guiding the carriage in a main scanning direction is provided to extend between a pair of opposing side plates, and a maintenance recovery mechanism for maintaining and restoring a condition of the recording head is arranged under the guide rod.
[Patent Document 2] Japanese Patent Laid-Open Publication No. 2001-158143
As a method for locating a home position of a carriage, a system as disclosed in Patent Documents 2 and 3 is often employed. This system causes a carriage to hit against a side plate holding an end of a guide rod and, with reference to this hitting position, move the carriage to a home position by performing predetermined operations.
[Patent Document 3] Japanese Patent Laid-Open Publication No. 2003-200570
Turning back to the image forming apparatus disclosed in Patent Document 1, when the recovery block is removed for the purpose of replacement (including repair), a carriage block integrally including a carriage and a guide shaft needs to be removed before removing the recovery block. This is because the image forming apparatus is configured such that the recovery block is removed via the upper side. Similarly, in the case of the image forming apparatus disclosed in Patent Document 2, it is impossible to remove only the maintenance recovery mechanism.
As can be seen, the image forming apparatuses as described above are not designed with enough consideration for on-site maintenance, and are not convenient from the standpoint of maintenance.